bot.js

(() => {
    //
    // GLOBAL VARS AND CONFIGS
    //
    //const whitelist = ['Fotos salvass', 'Teste ignore']
    const ignoreLastMsg = {}

    const jokeList = [
        `
        Husband and Wife had a Fight.
        Wife called Mom : He fought with me again,
        I am coming to you.
        Mom : No beta, he must pay for his mistake,
        I am comming to stay with U!`,

        `
        Husband: Darling, years ago u had a figure like Coke bottle.
        Wife: Yes darling I still do, only difference is earlier it was 300ml now it's 1.5 ltr.`,

        `
        God created the earth, 
        God created the woods, 
        God created you too, 
        But then, even God makes mistakes sometimes!`,

        `
        What is a difference between a Kiss, a Car and a Monkey? 
        A kiss is so dear, a car is too dear and a monkey is U dear.`
    ]


    //
    // FUNCTIONS
    //

    // Get random value between a range
    function rand(high, low = 0) {
        return Math.floor(Math.random() * (high - low + 1) + low);
    }

    // Call the main function again
    const goAgain = (fn, sec) => {
        // const chat = document.querySelector('div.chat:not(.unread)')
        // selectChat(chat)

        setTimeout(fn, sec * 1000)
    }

    // Dispath an event (of click, por instance)
    const eventFire = (el, etype) => {
        let evObj = document.createEvent('Events')
        evObj.initEvent(etype, true, false)
        el.dispatchEvent(evObj)
    }

    // Select a chat to show the main box
    const selectChat = (chat, cb) => {
        const title = chat.querySelector('.emojitext').title
        eventFire(chat, 'mousedown')

        if (!cb) return

        const loopFewTimes = () => {
            setTimeout(() => {
                const titleMain = document.querySelector('h2.chat-title').innerText

                if (titleMain != title) {
                    console.log('not yet')
                    return loopFewTimes()
                }

                return cb()
            }, 1)
        }

        loopFewTimes()
    }

    // Send a message
    const sendMessage = (chat, message, cb) => {
        //avoid duplicate sending
        const title = chat.querySelector('.emojitext').title
        ignoreLastMsg[title] = message

        //add text into input field
        document.querySelector('.input').innerHTML = message.replace(/  /gm,'')

        //Force refresh
        event = document.createEvent("UIEvents");
        event.initUIEvent("input", true, true, window, 1)
        document.querySelector('.input').dispatchEvent(event)

        //Click at Send Button
        eventFire(document.querySelector('.compose-btn-send'), 'click')

        cb()
    }

    //
    // MAIN LOGIC
    //
    const start = (_chats, cnt = 0) => {
        // get next unread chat
        const chats = _chats || document.querySelectorAll('.unread.chat')
        const chat = chats[cnt]

        if (chats.length == 0 || !chat) {
            console.log(new Date(), 'nothing to do now... (1)', chats.length, chat)
            return goAgain(start, 3)
        }

        // get infos
        const title = chat.querySelector('.emojitext').title + ''
        const lastMsg = (chat.querySelector('.last-msg') || { innerText: '' }).innerText //.last-msg returns null when some user is typing a message to me

        // avoid sending duplicate messaegs
        if ((ignoreLastMsg[title]) == lastMsg) {
            console.log(new Date(), 'nothing to do now... (2)', title, lastMsg)
            return goAgain(() => { start(chats, cnt + 1) }, 0.1)
        }

        // what to answer back?
        let sendText

        if (lastMsg.toUpperCase().indexOf('@HELP') > -1)
            sendText = `
                Cool ${title}! Some commands that you can send me:

                1. *@TIME*
                2. *@JOKE*`

        if (lastMsg.toUpperCase().indexOf('@TIME') > -1)
            sendText = `
                Don't you have a clock, dude?

                *${new Date()}*`

        if (lastMsg.toUpperCase().indexOf('@JOKE') > -1)
            sendText = jokeList[rand(jokeList.length - 1)]

        // that's sad, there's not to send back...
        if (!sendText) {
            ignoreLastMsg[title] = lastMsg
            console.log(new Date(), 'new message ignored -> ', title, lastMsg)
            return goAgain(() => { start(chats, cnt + 1) }, 0.1)
        }

        console.log(new Date(), 'new message to process, uhull -> ', title, lastMsg)

        // select chat and send message
        selectChat(chat, () => {
            sendMessage(chat, sendText.trim(), () => {
                goAgain(() => { start(chats, cnt + 1) }, 0.1)
            })
        })
    }

    start()
})()